I've been messing around with the D21G and finally got my project to run off it. (remember to change Serial.println to SerialUSB.println otherwise it freezes up :))
My PC running windows 8 wont recognize the D21G though. Guess its missing a driver, I tried the one you supplied in a link in the documentation page earlier, but it didnt work as it wasnt digitally signed or something. Now the link isnt working. Its working on my PC running Windows 10 though.
Secondly, how do I use the RTC on the D21G? Guess I need a library, but which one :)?
Regarding the driver, please look at my answer on this post: https://industruino.com/forum/help-1/question/early-d21g-adopter-need-some-documentation-326
Regarding the RTC: The model number is MCP79402, any library for the MCP794** series will work. Here's an example library which I have tested: https://github.com/radupietraru/MCP7940-RTC-Library Just remember to do a find and replace to replace "Serial" to "SerialUSB", otherwise you wont see any output on your serial monitor.
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